1. Field of the Invention
This invention is related to an improved structure of a heating drum for ironing machines.
2. Description of the Prior Art
Referring to FIGS. 1, 2 and 3, the conventional ironing machine generally includes a heating drum 1, a plurality of rollers 2, a canvas strap 3, a driving mechanism, and a steam generator.
The heating drum 1 is a metallic hollow cylindrical member and formed with two tubular members 120 at two ends which are connected to the driving mechanism and steam generator respectively so that the heating drum 1 will be driven to rotate at a constant speed and heated by the steam to produce heat temperature on its outer surface. An end of the heating drum 1 is provided with a drain hole 11. The rollers 2 are arranged around the heating drum 1 for guiding the canvas strap 3 thereby making the it act as a conveyor belt for transmitting bedsheets, clothes and the like to the outer surface of the heating drum 1 for ironing.
However, the heating drum 1 is of a smooth inner surface so that when the steam is cooled, it will be condensed into water drops which will then be accumulated at the bottom of the heating drum 1. Then, the heat of the steam passing through the heating drum 1 will be absorbed by the water thereby lowering the temperature of the steam and making it impossible to raise the temperature at the outer surface of the heating drum 1 to a desired value. The maximum temperature at the outer surface of the conventional heating drum is generally around 90-95.degree. C. thus making the clothing impossible to be dried completely.